The present invention relates to adjustment of a display position of an image in an electronic equipment for projecting an image onto a screen etc. and particularly, a projection type display unit provided with a position adjustment device which facilitates adjustment in a height direction and adjustment in movement of a housing.
In recent years, liquid crystal projectors as a projection type image display unit spread widely for uses as projectors in presentation and as projectors in home theaters. Under the present situation, liquid crystal projectors are made small in size and lightweight to be carried into places of presentation, rooms, in which home theaters are present, etc. to be put on desks in rooms.
On the other hand, a screen, onto which an image is projected, is generally installed in many cases higher than a position on a desk, on which a liquid crystal projector is placed, while depending upon an area of a place of presentation, a room, or the like.
Under such situation, liquid crystal projector is adjusted so that the front of its housing is lifted up in order that a displayed position of an image is projected onto a screen.
Arts for adjustment of a displayed position of an image in a projection type image display unit are disclosed in JP-A-2006-106487, JP-A-2007-33874, and JP-A-2008-116577.
For details, an adjuster device described in JP-A-2006-106487 includes a height adjusting shaft provided on an upper portion thereof with a worm and provided on a lower portion thereof with a knob, and an adjusting leg provided with a rack, which meshes with the worm, the knob being turned to adjust a amount, by which the height adjusting shaft projects. Since a amount of projection is adjusted by a worm and rack arrangement, it is possible to finely adjust the amount of projection.
Also, a projected position adjusting device of a projector described in JP-A-2007-33874 includes a movable leg provided to be able to advance and retreat with respect to a bottom plate of a projector housing, and a amount of advancement and retreat is given by an electrically driving unit fixed to the projector housing.
Also, a height adjusting device described in JP-A-2008-116577 includes a gear mechanism for adjusting a projection amount of an adjustment leg, and an adjustment knob, which is formed by a bevel gear, is provided on a leg guide, which guides the adjustment leg, whereby the adjustment knob can be manipulated in the same direction as a direction, in which adjustment of a projection height is desired.